Nearly 75 years after it was fought, D-Day remains one of the most vividly recalled battles in history. It was also one of the most decisive. There are those who will argue that the Allies would have won World War II regardless of the outcome of the Battle of Normandy. Indeed, similar arguments are made for most decisive battles. Two years ago, I wrote about the Battle of Midway, on the 75th anniversary of that campaign, and argued that a defeat there would have been disastrous to the global balance. But some readers rejected this, saying that, even if the U.S. had been defeated, it would have deployed ships into the Pacific and recovered. That might well be true, but as I will try to show, the invasion of France’s Calvados coast was a turning point in the war. Had it failed, the Allies likely would not have been able to recover.

Far From Over

The pivot was the Soviet Union. By the time the D-Day invasion was launched, the Soviet Union had been fighting the Germans for three years. Germany had conquered most of the Soviet heartland and its treatment of the occupied areas was barbaric. For the first five months of the war, it seemed likely that the Soviets would lose. Only an extraordinary effort by the Red Army, aided by supplies from the United States, allowed them to stabilize the front and return to the offensive. But when D-Day was launched, the Soviets were still over 1,000 miles from Berlin. For them, the war was far from over.

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For the British and Americans, the continued Soviet participation in the war was essential. The Soviets had tied down the bulk of the German army for years and bled it dry. Without the Soviets’ involvement in the war, an Allied invasion of France would have been impossible as Germany could have massed overwhelming force and shifted troops to Italy, blocking access from there.

But the Soviets believed that the Allies had deliberately delayed an invasion of France to allow the Germans and Soviets to weaken each other so that American and British forces could come ashore with minimal opposition and fight their way into Germany, and perhaps beyond. The Soviets had repeatedly asked for a second front in 1942 and 1943. The Allies responded with a Mediterranean campaign, first in North Africa and then in Italy. From the Soviets’ perspective, this was merely a gesture – they were fighting for their lives in Stalingrad, and the Mediterranean operations were not large enough to force the Germans to redeploy troops away from their eastern flank. And so, the basic correlation of forces between Germany and the Soviets remained as it was.

The Americans and British said they simply weren’t ready for an invasion. Stalin didn’t dispute that but argued that even a failed invasion would have forced Hitler to re-evaluate the vulnerability of his troops in the west and shift some forces there. A reduction of German forces and redirection of logistical support would have increased the likelihood of a Soviet victory and reduced the damage to Soviet forces. Stalin was left with the impression that the Western Allies wanted the Germans to do maximum damage to the Red Army and that the Americans and British were unwilling to carry out a doomed spoiling attack because they were unwilling, for political reasons, to absorb a fraction of the casualties the Soviets were absorbing.

The two sides didn’t trust each other. The British and Americans were appalled at the Hitler-Stalin pact of 1939, while the Soviets were angered by the Americans’ willingness to enter the war only after the Japanese attack on Pearl Harbor and Hitler’s declaration of war on the United States. The U.S. built up its forces slowly and deliberately, minimizing exposure to minor battles in the Pacific and major thrusts at nothing important. Stalin believed that Roosevelt wanted a weak Soviet Union to emerge and that, after the Soviets destroyed the Wehrmacht, the U.S. would seize Europe and the British Empire. He once said that Churchill was the kind of man who would pick your pocket for a kopeck but Roosevelt was the kind of man who would steal only big coins. From Stalin’s view, Churchill was governing a declining power while Roosevelt, brilliant and utterly ruthless, was in charge of the future hegemon of the world.

A Hard Pill to Swallow

There is ample evidence that Soviet and German representatives had met in Stockholm for serious talks. Hitler saw Stalin’s opening as a sign of weakness. Understanding the tension between the Soviets and the Americans and British, he didn’t believe in 1943 that they could mount an invasion. Since Stalin himself had doubts, Hitler drove a hard bargain, demanding that Germany retain the land it had already won, particularly Ukraine. The talks broke down, though contacts seem to have continued.

Had the Allies not invaded Normandy in 1944, it is reasonable to assume that Stalin, whose troops were still fighting far inside their own country, would have accepted the deal with Hitler, since he likely could not continue fighting without a western front or at the very least could not regain the territory on his own. Churchill, it should be noted, was never enthusiastic about the invasion, either because he feared the resulting losses would be the end of the British army or because he wouldn’t have minded if the German-Soviet war continued so the Allies could intervene at the last minute, while nibbling at Greece. Either way, Roosevelt rejected Churchill’s view, sensing that the Soviets would make peace without an Allied invasion.

Thus, the invasion was launched in June before the campaign season was lost. Had the Americans and British not seized the opportunity to invade at that time, or had the campaign failed, they would have had to wait until the following spring to mount an invasion. And by then, the Soviets may well have been forced to make peace, giving the Germans a far denser defense along the French coast that would almost certainly have made an invasion impossible. Alternatively, the Allies could have tried to attack Germany through Italy or the Balkans – through the Alps. But with the Soviets out of the war, the Germans would have gained a massive advantage. A German-Soviet truce would have been hard for the Soviets to swallow, but if D-Day had failed and if the Allies couldn’t mount another operation for another year, Stalin may not have had any other choice. He couldn’t win the war on his own.

The Americans would have had the atomic bomb within a year, and I don’t doubt they would have used it while the war raged. But if there was peace in the east, and little fighting in the west, would the U.S. really nuke Berlin or Munich and then try to occupy Germany? I don’t believe it would, but I could be wrong.

D-Day was the decisive battle of World War II not only because it unleashed the full strength of the Anglo-American forces but because it forced Hitler to fight on two fronts, easing the Soviets’ positions sufficiently for a confident advance. Had the invasion not taken place or had it failed, Stalin would likely have made peace with Hitler. Germany would have grown stronger, unless the U.S. and Britain wanted to wage war alone, which I don’t think they did. In the end, Hitler was right when he said Germany’s fate would be decided in France – on the Calvados coast in Normandy, to be exact.

D-Day and Stalin